ORAU hosted a workshop sponsored by the NIH and ORAU to address the question, "Is the Marmoset an Experimental Model forthe Study of Gastrointestinal Disease?". This program, held in April, 1984, considered the animal resource, colitis, and colon cancer in the cotton-topped marmoset. Participants discussed the overall value of the marmoset for the study of GI diseases. Many of the participants have initiated collaborative studies with ORAU to conduct the following studies involving the NCI animals: studies of coronavirus in the etiology of colitis; transformation of marmoset lymphocytes with HTLV-I and HTLV-II; studies of colon cancer; cytogenetic characterization of peripheral lymphocytes of marmosets; and determination of relative susceptibility of these marmosets to developing colon cancer.